Originally an expansion for Exploding Kittens, the most successful Kickstarter project ever, that contained cards that were too horrific and/or incredible to be included in a kid-safe version. As a stretch goal, this was turned into a stand-alone game that can be combined with the standard Exploding Kittens deck. If you combine the two decks, you can go up to 9 players (or 10 players with the Imploding Kittens expansion).